5. which of the following statements most accurately differentiates potential and kinetic energy?
a. any object that has motion has kinetic energy, while any object not in motion but with the potential to do work has
b. any object that has motion has potential energy, while any object not in motion but with the potential to do work has
c. kinetic energy is a form of mechanical energy, while gravitational potential energy isn't
d. gravitational potential energy is a form of mechanical energy, while kinetic energy isn't
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A. Any object that has motion has kinetic energy, while any object not in motion but with the potential to do work has potential energy

Explanation:

Both kinetic energy and potential energy are part of the mechanical energy of an object, their origin is different. In fact:

- The kinetic energy of an object is the energy due to the motion of the object. It is given by

where m is the mass of the object and v its speed. As we see from the equation, when an object is stationary, v = 0, and therefore it has no kinetic energy.

- The potential energy of an object is the energy stored as 'potential' to do work. There are several types of potential energy. For instance, gravitational potential energy is the potential energy that an object possesses in a gravitational field, and it is given by

U = mgh

where m is the mass of the object,  g the acceleration of gravity, h the height of the object with respect to the ground. When the object is released from its position, it falls freely towards the Earth, and this energy is converted into kinetic energy.

b.a device that inputs heat into a cool object